Apparatus for suspending glass plates



April 25, 1939. cs, P. DESPRET 2,156,011

APPARATUS FOR SUSPENDING GLASS PLATES Filed March 23, 1936 2 Sheets-Sheet l P 1939- G, P. DESPRET APPARATUS FOR SUSPENDING GLASS PLATES 2 Sheets-Sheet 2 Filed March 23, 1936 Patented Apr. 25, 1939 V APPARATUS FOR SUSPENDING GLASS PLATES Georges Paul Despret, Paris, France, assignor to The American Securit Company, Washington, D. 0., a corporation of Delaware Application March 23, 1936, Serial No. 70,479

In France March 28, 1935 2 Claims. (CI. 49-14) During the tempering step of glass plate, sheets form by bulging or torsion. The frame stops or other similar products the sheets are generally thus hold the sheet perfectly flat. suspended at their upper part by grippers of the Other features will be apparent from the folso-called frog leg type, the advantage of this lowing description. method of suspension consisting in that a very On the accompanying drawings, given by way 5 small zone or surface of the sheet is engaged. of example:

The grippers themselves are attached to 9. Sup- Figure 1 is a front elevation of the assembled port which is generally movable, for example a improved suspension device. swingletree bar. Figure 2 is a profile. I The sheets thus suspended are carried into a Figure 3 is a partial, enlarged section on line 10 heating furnace of any suitable construction in 3-3 of Fig. 1. which they are carried to a temperature near the Figures 4 and 5 are partial views, in elevation softening point. When this temperature has and plan, of the frame locking device in operabeen attained the sheets are withdrawn from tive position. I the furnace and carried into a cooling apparatus Figure 6 is a partial section on line 6-6 of v where they are suddenly cooled. In this manner Fig. 5. the sheets pass into the so-called tempered state, Figure 'I is a diagrammatic front elevation of through which they are given new properties, a modification.

such as resistance to fracture, to heat, etc. Figure 8 represents two positions of the frame During the operation the glass sheets suspendvery diagrammatically. 20 ed as before described may become deformed According to the construction illustrated on through the action of the heat, particularly if Figs. 1 to 6, the sheet I, of glass or other material the sheetsare of great dimensions. is suspended bygrippers of the frog leg type,

The present invention relates to a suspension in which the two jaws are provided with sheet apparatus for glass plate or sheets, panes or slmiengaging points 3 and are pivoted at 4 to each 25 lar products, applicable particularly in the temother, and at 5 and 6 to the arms of a compass 'l, pering operation, for the purpose of preventing so that the whole forms a deformable quadrideformation or deterioration of the suspended lateral. sheet or plate. The grippers are suspended by the top of their In accordance with the invention the grippers, compass from a swingletree or bar 8 through a 30 preferably of the frog leg type are connected resilient device. to their support or swingletree by means of a In the exemplary embodiment shown each of resilient device. the precedingly described grippers is connected By means of this resilient device, on release by a rod 9 to a rod l0, terminating at its lower 5 of the gripper support above, in raising the susend in a hook II and at its upper end in a shoulpended sheet after theheating, the grippers are der formed, for example, of a washer 12 (Fig. 1). prevented from closing suddenly, through the The rod l0 bears through this washer, from action of inertia, due to the mass of the sheet. Jove, downwardly on a spring l3 or other resiland sharply impressing their points into the lent or cushioning member. This spring l3, or glass, or sheets of other material and thus create similar member, is seated in a tube or casing I 4 40 deformation in the vicinity of these points. The and rests on the base #5 in the lower end of said resilient suspension thus precludes such local de- Casing- At e pp end the tu e Ca M formation. carries a plug l6 which is connected by means The suspension device is completed preferably of a hook n to an attaching member of the a swingletree.

i i i i int nded by a frame or chass S having r g d s des e As previously stated, by means of the resilient to encompass temporarily one or more sides of suspension described or modifications thereof, the suspended plate this frame comprising stop when the sheet is raised after being heated, the members mounted oppositely in pairs between action of inertia, due to the mass of the plate, which the corresponding edge of the Suspended is overcome, and thus the grippers are prevented 50 plate ehgages' from suddenly closing and forcing their points These Stops Prevent deforma'hon of the Sheet 3 into the plate to such depth as to cause local during their heating. As known, the heat being deformation concentrated at the centre of the furnace, the The mounting described provides resiliency not glass plates, sheets, etc. have a tendency to deonly vertically, but also torsionally in a horizon- 55 tal plane, that is, the plate I may turn within certain limits about a vertical axis without resultant deformation, as would be the case if the distances ab -a'b' were invariable and equal. In fact, due to the resilient suspension, the attachments connecting the points a, b and a and b may vary in length and follow the geometric length variations of the distances ab and a'b', due to said oscillations of sheet I, thus preventing the application of the entire force of the grippers on the sheet.

This second advantage of the resilient suspension is, also of importance, the device being completed preferably by a frame intended to prevent or minimize all warping of the plate and at the same time any oscillation of the latter, which would cause inconvenience, as described hereinafter, atleast during the critical period at the beginning of the heating before the tempering.

This rigid frame or chassis I9 is formed, for example, by four tubes I9 braced together pairwise at 20 and connected below by a bar 2I (Figs. 1 to 3).

Affixed to this bar connection 2I are a certain number of guides, which may consist, for example, of simple screws oppositely disposed in supportv 23, (Figs. 1 to 3).

Without exceeding the scope of the invention the guides may also be formed of .any other similar arrangement, for example, rods carried by screws, etc.

The distance between two opposite screws is regulable according to the thickness of the sheets I to be tempered.

Each tube I9 of the frame or chassis I9 may slide in grooves 24 (Figs. 5 and 6) provided in the horizontal frame members of the swingletree 8.

The position of tubes I9 relative to swingletree 8 may be fixed by any kind of retaining device.

For example, according to the embodiment represented on Figs. .1-4-5-6, the retaining device is formed by the grippers 25 with the retractile spring 26. Grippers 25 are mounted oscillatably at 2i on swingletree 8. It is apparent that through the action of spring 25 the grippers 26 hold the tubes I9 against the swingletree t.

Notches 28 (Fig. 6) are also provided in the tubes at suitable intervals, so that the frame may remain suspended at different heights relative to the swingletree. Y

The descent of frame I9 after release from the grippers 25 is limited by stops 46 (Fig. l), which are regulable in position.

The following is the improved method of heating, in accordance with the invention.

The sheet I of glass, plate, or similar material is first hooked to the grippers 2, the frame is is then carried into a position such that the bottom of the sheet is engaged between the screws 22.

The sheet I thus held by the rigid frame is then lowered into the furnace to be carried therein to the suitable tempering temperature.

When the temperature of the sheet has reached a certain value, the order of 450 C. for example I have found that, the tendency of the sheet to deform no longer exists. Thus, when this temperature is attained, the frame is released by manipulating the retaining grippers 25, so as to lower it for a degree regulated by the stops 40, and so that the bottom of the sheet is no longer engaged between stops 22. This release of the chassis is necessary, because if left in its initial position badly tempered zones or nodes would be produced in the sudden cooling by an air let, these zones being at the point of screws 22.

On the other hand, notwithstanding that the pressure of the cooling air is exerted on both surfaces in an approximately equal manner, the glass plate oscillates slightly during the cooling, which would bring it in contact with the screws 22 in the form or repeated shocks, which might make impressions or imprints in the glass.

It is evident that other means for preventing deformation of the glass sheet in accordance with the invention may be realized, without departing from the scope thereof; for example, the guides may be distributed not only over the lower strip of the plate, but over the entire periphery. In such case the sheet is released before the tempering by any suitable mechanism.

Figure '7 shows by way of example a mechanism of this type. According thereto the tubes I9 on each side of the sheet, carrying the guides are pivoted at 29 and 30. Also, two arms 3I and 32, pivoted together at 33, are connected with the tubes II! by the pivots 34 and 35.

The chassis I9 is locked against the lower part of swingletree or bar 8 by a locking device 25, of any kind, for example of the type described.

When the chassis I9 is released it opens under the action of a spring 36, for example, which raises the arms 3I and 32 at 3| and 32' (Fig. 8) and removes the guides'from the three edges of the sheet. The glass sheet is suspended from the bars 3I-32 by the gripping devices 3. Guiding forks or yokes 22 straddle the top edge of the sheet and serve to guide it and maintain it against distortion. When the bars 3I-32 are raised the yokes 22 move upwardly to a point above-the top edge of the glass sheet. Fig. 8 shows the chassis in the open position. The longitudinal tubes I9 have passed into the position I9.

It is, of course, to be understood that the invention is not limited to the embodiments illustrated and described, which are given by way of invention, what I tion, side portions pivoted to the bottom portion,

means carried by said frame for maintaining the sheet against lateral movement and means engaging the side portions of the frame for separating the upper end thereof to remove the side portions of the frame out of guiding position in respect to the glass sheet.

2. In apparatus for suspending glass sheets, the combination of a supporting bar, means for suspending the sheet from said bar, a frame associated with said bar and provided with a bottom portion, side portions pivoted to the bottom portion, means carried by said frame for maintaining the sheet against lateral movement, means engaging the side portions of the framefor separating the upper end thereof, means connecting the side portions of the frame above the sheet of glass, glass suspending devices associated with the last named means, and means engaging the side portions of the frame for separating the upper end to remove the side portions of the frame out of guiding position in respect to the glass sheet and to lift the sheet in respect to the bottom portion of the frame.

GEORGES PAUL DESPRET. 

